BAW components usually comprise a layer stack with a piezoelectric material sandwiched between two electrodes. When an RF signal is applied to the electrodes, an acoustic resonance can be formed if means for confining acoustic energy in the stack are present. Mirror systems under the stack or a cavity under the stack are typical means for confining the acoustic energy. Utilizing acoustic resonances, band pass filters or band stop filters can be established.
Conventional BAW components comprise AlN (aluminum nitride) as a piezoelectric material. However, the band width of pass bands or stop bands of BAW components are limited. What is needed is a BAW component providing a larger band width.